Consider the prune

The world's most famous prune is French, but California grows its clones. Is there a difference between them?

Topics: The Art of Eating, Food,

Consider the prune

The most famous prune in the world, the pruneau d’Agen, has been a celebrated product of southwest France since at least the 1500s, outliving — and even thriving because of — several nearly existential threats.

The variety of plum grown to be dried into these prunes is the Prune d’Ente, chosen after the winter of 1709 killed many trees, requiring widespread replanting. Its taste was superior to that of previous varieties, its fruit was larger and higher yielding, and it was well-adapted to the region. Agen prunes were a huge success, heavily exported, until the two world wars of the 20th century devastated production, creating another chance for selecting and propagating especially fine specimens. From 1943 to 1949, French government researchers on bicycles, knowing that the variety embraces many clones, selected 60 outstanding trees and reduced those to the six best. One of them, assigned the number 707, now makes up roughly three-quarters of all the Prune d’Ente planted in France, which under the Indication Géographique Protégée, awarded by the EU in 2002, is the only variety permitted.

The Central Valley of California is the world’s largest producer of prunes, and their quality, too, can be high. Genetically, there may not be a great difference between Agen prunes and those raised in California. The U.S. variety is French Improved, descended from examples of Prune d’Ente imported in the mid-19th century. (The 707 didn’t do well in California.) Differences in taste may come from differences in climate and in pruning. The latitude of the Agen orchards, followed around the globe to North America, runs a little north of Toronto, and the French trees, which receive significant rain during the growing season, are pruned to be open, so the fruit is exposed to the sun. The Central Valley trees, in contrast, grow in much greater heat and receive little or no rain; they require irrigation and are pruned so the foliage will protect the fruit.

Besides effects of clones and location, any edge of flavor in the Agen prunes might be due to slightly greater ripeness at harvest. Not that there is a difference in goal, but the Agen growers may achieve it more often. In California, the time to harvest is determined by measuring the softness of the fruit, which is linked to sweetness; growers aim to pick when resistance to pressure, applied to the fruit with a penetrometer, falls to between three and four pounds. But in France, explains Jean-Michel Delmas, a grower, farm-union activist, and historian of the pruneau d’Agen, the growers measure the sweetness directly with a refractometer, looking for 21 degrees Brix — each degree equaling approximately 1 percent sugar — and sometimes achieving much more. (Ripeness often used to be determined by the plums themselves, which fall from the tree as they become ripe. Growers would spread straw on the ground as a cushion to prevent bruising.) The harvest in nearly all the Agen plum orchards is now mechanized, and the machines, which shake the trees and catch the fruit, pass four to seven times, as the fruit ripens. In California, similar machines harvest much more aggressively, passing just once to gather all the fruit from the tree.

Long ago, the Agen plums were dried in the sun or on farms in warm bread ovens. Today mechanical driers reduce the moisture to 21 to 23 percent for keeping, and then in a recent innovation that quickly became universal in the region, before packaging they are rehydrated to 35 percent. That gives a more luscious consistency, and there’s no longer a need to soak before use.

Most California prunes are now pitted, but only about half the French ones are. Although French technical experts say that last-minute pitting before packaging has no effect on flavor, Delmas thinks differently. “In fact,” he says, “a large part of the flavor comes from the presence of the pit. Without it, the plum loses the heart of its aroma.” He associates the pit with a violet perfume. Among the local dishes he eats frequently are prunes with rabbit or with pork as well as with beef, in a daube, a red-wine braise.

To ensure safekeeping, producers of pruneaux d’Agen now add the preservative sorbic acid or its relatives or they pasteurize at 70 degrees C, giving a slightly darker color and a more concentrated, caramel flavor. When I made a side-by-side comparison of some Agen prunes (pitted, no preservatives) with two California brands (pitted, with preservatives), the Agen were softer and moister, thinner-skinned, sweeter, with slightly fruitier, somewhat stronger flavor and a longer aftertaste. But, alas, the Agen prunes cost nearly double.

Click here to read more from the Art of Eating on Salon, and visit artofeating.com

Next Article

Related Stories

Featured Slide Shows

The week in 10 pics

close X
  • Share on Twitter
  • Share on Facebook
  • Thumbnails
  • Fullscreen
  • 1 of 11
  • Lisa Montgomery embraces her nephew Thursday after a tornado tore apart her home in Cleburne, Texas. The twister killed six people and destroyed entire swaths of the North Texas town.
    Credit: AP/LM Otero

  • Jack McMahon, the defense attorney for abortion doctor Kermit Gosnell, speaks outside the Criminal Justice Center in Philadelphia Tuesday. His client was convicted of killing three babies in his clinic, and will serve multiple life sentences.
    Credit: AP/Matt Rourke

  • A photo taken Monday captures Vice President Joe Biden's response to a Milwaukee second-grader's innovative proposal to end America's epidemic of gun violence. This guy!
    Credit: AP/Jenny Aicher

  • Sen. Rand Paul, R-Ky., flanked by a grouper-eyed Michele Bachmann, addresses the IRS' admission that it targeted Tea Party groups in advance of the 2012 election. In an op-ed for CNN Thursday, the Kentucky senator slammed the president for his faux outrage.
    Credit: AP/Molly Riley

  • Ousted IRS chief Steven Miller is sworn in on Capitol Hill Friday. Miller testified before the House Ways and Means Committee on the extra scrutiny the agency gave conservative groups applying for tax-exempt status.
    Credit: AP/J. Scott Applewhite

  • Attorney General Eric Holder pauses as he testifies on Capitol Hill before the House Judiciary Committee Wednesday. Holder is under fire, among other things, for the Justice Department's gathering of phone records at the Associated Press.
    Credit: AP/Carolyn Kaster

  • O.J. Simpson sits during an evidentiary hearing at Clark County District Court in Las Vegas, Nev., Thursday. Simpson, who is currently serving a nine-to-33-year sentence in state prison for armed robbery and kidnapping, is using a writ of habeas corpus to seek a new trial.
    Credit: AP/Las Vegas Review-Journal/Jeff Scheid

  • Major Tom to ground control: On Sunday astronaut Chris Hadfield recorded the first music video from space, a cover of David Bowie's "Space Oddity."
    Credit: AP/NASA/Chris Hadfield

  • When it rains it pours. President Barack Obama speaks during a news conference Thursday with Turkish Prime Minister Recep Tayyip Erdogan, inexplicably inspiring an #umbrellagate Twitter meme.
    Credit: AP/Jacquelyn Martin

  • A smoke plume rises high above a road block at the intersection of County A and Ross Road east of Solon Springs, Wis., Tuesday. No injuries were reported, but the the wildfire caused evacuations across northwestern Wisconsin.
    Credit: AP/The Duluth News-Tribune/Clint Austin

  • Recent Slide Shows

  • Share on Twitter
  • Share on Facebook
  • Thumbnails
  • Fullscreen
  • 1 of 11

Comments

9 Comments

Comment Preview

Your name will appear as username

You may use these HTML tags and attributes: <a href=""> <b> <em> <strong> <i> <blockquote>